This Handbook on Emergency Telecommunications is written to serve as a close companion to those involved in the noble work of providing as well as using telecommunications for disaster mitigation and relief. It simplifies and demystifies the complex technical issues that characterize the fast evolving field of telecommunications, especially in this era of convergence and emergence of next-generation networks. While designed to be simple, the Handbook is comprehensive, compact and contains useful factual information that is concise and organized for easy access, in particular by practitioners.